Question

A parallelogram has an interior angle measuring 81º. Which MUST also be the measure of an interior angle of the

parallelogram?
A)9°. C)49°
B)19° D)99°

Answer 1

D)99 degrees

Explanation:

The answer is D. All the angles in any quadrilateral add up to 360 degrees. And since the figure is a paralledlogram, for each angle there is another angle with the same measurement. So 81 + 81 + x + x = 360 which gives us 162 + 2x = 360. If you solve for x you get 99 degrees.